... etc.c. ASTM/AISI Standard10#(ASTM a106/53 Gr.B,A192,A179-C),20#(ASTM A106/53 Gr.B, A178-C,A210-A ... -1,A315-B,AISI1020),45#(AISI1045), ... 16mn(ASTM A210-C) etc.Usageboiler use, ... and mark on the pipepayment termT/T or L/C at sight.Methodcold drawning, hot rolling or hot expanding ...